(a) Technical Field
The present disclosure relates to a system and method of controlling charge of a battery for a vehicle. More particularly, the present invention relates to a system and control method for reserved charge of a vehicle battery, which may complete a charge of a battery in advance based on a vehicle operation time set by a driver.
(b) Background Art
Recently, developments have been made to supplying an environmentally-friendly vehicle globally, which uses an electric motor as a driving source of a vehicle, and to a technology of an electric energy storage device, such as a battery, which is a power source of the environmentally-friendly vehicle. Accordingly, research has been conducted regarding development of an internal/external device and charging equipment for a vehicle battery, expansion of a charge infrastructure, and the like.
As is well known, an environmentally-friendly vehicle, such as an electric vehicle or a hybrid vehicle, includes an electric motor as a driving source of the vehicle, a motor control unit (MCU, including an inverter) configured to drive and operate the electric motor, a battery configured to supply power for driving the electric motor, and a charging device within the vehicle configured to charge the battery, and includes a charging port for connection between the vehicle and an external charging device, and the like.
A battery management system (BMS) configured to monitor and manage a state and an operation of the battery is mounted within the environmentally-friendly vehicle, and collect battery state information, such as a voltage, a current, a temperature, a state of charge (SOC) and the like of a battery pack, and provide the collected battery state information to another controller inside and outside of the vehicle to use the collected battery state information to operate the vehicle or the charge. A battery of an environmentally-friendly vehicle, such as an electric vehicle (EV) and a plug-in hybrid electric vehicle (PHEV), may be charged at a substantially low speed by connecting an alternating current (AC) charging power source (e.g., low-speed charger) to the vehicle or charged at a substantially high speed by connecting a direct current (DC) charging power source (e.g., high-speed charger) to the vehicle.
When the low-speed charger supplies AC power to the vehicle, an on-board charger (OBC) within the vehicle converts AC power to DC power to charge the battery. In the meantime, the high-speed charger converts AC power to DC and supplies the DC to the vehicle, and is directly connected to the battery within the vehicle to supply a substantially high current, thereby completing the charge of the battery within a substantially short period of time. To charge the battery, a connector of an external charger (e.g., the low-speed charger or the high-speed charger) is connected to a charging port of the vehicle, and charging power of the charger may be supplied through the connection of the connector.
A plurality of terminals, such as a communication terminal, a communication power supply terminal, and a ground connection terminal for communication connection with the vehicle, are provided at the connector to supply charging power, in addition to a power supply terminal. When reserved charge, which may automatically complete charge of the battery in accordance with a desired vehicle operation start time when a driver connects the vehicle to the external charger, to charge the battery of the vehicle at a substantially low speed or a high speed after the operation of the vehicle, is performed, convenience of the user may be considerably improved.
However, to perform the reserved charge, there is a need to be aware of a time consumed for charging in the vehicle, and when all of specifications of the external charging power sources (the low-speed charger or the high-speed charger) are the same, and when a predetermined uniform current and voltage is output from the external charging power sources, a time consumed for charging may be more easily estimated.
However, the specifications of the power sources of the external chargers for charging the vehicle are may not be uniform, and even though the specifications of the power sources are the same, output states of a current, a voltage, and the like actually output from the charger may be different according to a system power supply connected with the charger. For example, even though the specifications of the power sources of two external chargers are the same with 100 kW, there may be a difference in a current and a voltage which may be output when the two external chargers charge the battery. An external charge power source (the low-speed or high-speed charger) in accordance with a design specification of the battery pack may be connected to the vehicle during the charge of the battery, but an external charging power source with a lower power supply system may also be connected with the vehicle.
As described above, the specifications and the output states, such as the output current and voltage, of the external charge power sources for charging the battery may be different, and a time consumed for charging of the battery may be different according to a specification or an output state of the connected power source. Since an estimation of a time consumed for charging may be difficult as described above, a reserved charge technology may be difficult to apply, which enables the battery to be accurately and completely charged at a time desired by a driver, to an environmentally-friendly vehicle, such as an electric vehicle or a hybrid vehicle.
When an air conditioning function, used to adjust an internal temperature of a vehicle in advance before a driver and a passenger enter the vehicle, is applied to an environmentally-friendly vehicle, in addition to the reserved charging function, it may be possible to maximize convenience of a user, but a reserved air conditioning technology associated with the reserved charge has not been suggested.
The above information disclosed in this section is merely for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.